I was just searching my Google Drive account for a document containing the word 'internet' and the top hit was a screenshot i took of instructions of how to configure the DNS settings to use for a proxy VPN service - which is littered with the word 'internet'

The file is named Screen Shot 2013-06-23 at 21.29.53.png and its a png so there is no static text in there (although it is a screen shot if text).

Does Google Drive OCR images to check for the text inside of them to make them available in search, or is this just a lucky coincidence ?